msan: Handle musttail calls

[oota-llvm.git] / lib / Transforms / Instrumentation / MemorySanitizer.cpp

diff --git a/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index 3df1d15741203f62d22105a34df2946768942ec5..643faacc70053a22eb3c9a4daee3750def12be8b 100644 (file)
--- a/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -2356,6 +2356,12 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
       VAHelper->visitCallSite(CS, IRB);
     }
 
+    // If this is a musttail call site, we can't insert propagation code here.
+    // The return type of the caller must match the callee, so the shadow should
+    // already be set up for an immediate return.
+    if (CS.isMustTailCall())
+      return;
+
     // Now, get the shadow for the RetVal.
     if (!I.getType()->isSized()) return;
     IRBuilder<> IRBBefore(&I);
@@ -2389,6 +2395,10 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
   }
 
   void visitReturnInst(ReturnInst &I) {
+    // Don't propagate shadow between musttail calls and the return.
+    if (I.getParent()->getTerminatingMustTailCall())
+      return;
+
     IRBuilder<> IRB(&I);
     Value *RetVal = I.getReturnValue();
     if (!RetVal) return;